Thinking about the physical interaction between people and machine that I witness everyday, I have to say the first one that comes to mind is neither something I witness nor does it involve a person. It involves a dog, specifically the one next door in the adjacent apartment, and a mechanism his owner has to calm his barking. I live on the first floor of an apartment building and when someone enters generally this dog from next door (speak of the devil, he's barking now) likes to bark to "greet" the person entering. Well, I suppose at some point in time the owner realized this barking could go on for too long and installed some sort of device that buzzes (perhaps shocks the dog) from inside the apartment. Soon after the first bark, you hear the buzz. It doesn't seem to work very well (the dog is currently still barking about a minute into the buzz). But what is interesting to me about this interaction is that someone has spent time designing a machine that is meant to alter the behavior of an animal by delivering negative feedback, aka punishment. Through this supposed conditioning a "reverse" interaction is occuring: the machine (technically) insititues the interaction, and the animal responds. I wish I could see it work.